Toelichting:
Program note (English): [Première: June 20, 2001 - Stadsschouwburg, Amsterdam - Asko Ensemble, Stefan Asbury (cond.), live performance to film #23.2 by Joost Rekveld (Holland Festival)] - Book of Mirrors is a collaboration project by abstract film maker Joost Rekvel and composer Rozalie Hirs. Its subjects are mirror images and prime numbers which are kaleidoscopically translated to all levels; they appear in the global time structure of both film and music, in the lengths within the movements of film and music, in frequency relationships and local pulse relationships within film and music, determining basic generating intervals and leading to further pitch materials (i.e. chords) in the music, as well as the use of colour in the film. Book of Mirrors investigates the psychoacoustic phenomenon of frequency addition, naturally occurring in the human auditory system during simultaneous perception of two pitches. Basic generating intervals are translated into chords through frequency calculations(frequency additions, ring modulation) performed in Open Music software of lrcam, France. - ROZALIE HIRS